This invention relates to an arrangement for collimation of light emanating from a laser light source, including a laser light source with a plurality of essentially linear emission sources, which are located in at least one row next to one another, and collimation means, with a number of collimation elements, these collimation elements being able to collimate the light emanating from the emission sources in the direction which corresponds to the direction of the row. Furthermore, this invention relates to a beam transformation device for one such arrangement.
An arrangement of the aforementioned type is suited for collimation of the light emanating from a laser diode bar. For collimation of the fast axis divergence of the light, emanating from the laser diode bar, a cylinder lens, which extends with its cylinder axis in the direction of the row of adjacent emission sources of the laser diode bar, can be used. For collimation of the slow axis divergence of the light, emanating from the laser diode bar, a cylinder lens array can be used, which has individual cylinder lens sections which are used as collimation elements, with cylinder axes aligned perpendicular to the direction of the row of emission sources. Since generally the emission sources of a laser diode bar are arranged equidistantly to one another, and at the same time, also the individual collimation elements of such a cylinder lens array are located equidistantly to one another, in the art, the light emanating from one of the emission sources is collimated by exactly one of the collimation elements with respect to the slow axis. Due to the fact, that there are very small distances between the individual emission sources of a laser diode bar, and the distances between the individual collimation elements must be chosen to be comparatively small, production engineering problems arise.
One object of this invention is to devise an arrangement of the initially mentioned type which enables a greater distance of the collimation elements to one another, at the same distance of individual emission sources of the laser light source to one another.
This object is achieved in that the arrangement includes a beam transformation device which can transform the light emanating from at least two emission sources, such that the light emanating from these at least two emission sources strikes exactly one collimation element and is collimated. In particular, the light emanating from exactly two emission sources will hit exactly one collimation element and is collimated by it. As a result of this beam transformation device, the distance of the individual collimation elements can thus be chosen to be twice as great as in arrangements from the existing art, so that the production costs for an arrangement are distinctly lower.
It can be provided that the collimation means include at least one lens for the collimation of the fast axis divergence and collimation elements for collimation of the slow axis divergence, here the beam transformation device being located between the aforementioned at least one lens intended for fast axis divergence and the collimation elements for slow axis divergence.
It can be provided that the collimation means include a cylinder lens array with cylinder lens sections which are used as collimation elements, with cylinder axes which extend especially in one direction and which are aligned perpendicular to the direction of the row and to the middle propagation direction of the light beams. These collimation means are used for collimation of the slow axis divergence of the light beams incident on it.